US20140106097A1 - Process for the production of biodegradable films having improved mechanical properties - Google Patents
Process for the production of biodegradable films having improved mechanical properties Download PDFInfo
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- US20140106097A1 US20140106097A1 US14/036,215 US201314036215A US2014106097A1 US 20140106097 A1 US20140106097 A1 US 20140106097A1 US 201314036215 A US201314036215 A US 201314036215A US 2014106097 A1 US2014106097 A1 US 2014106097A1
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- Prior art keywords
- biodegradable
- film
- process according
- stretching
- aliphatic
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Classifications
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C55/00—Shaping by stretching, e.g. drawing through a die; Apparatus therefor
- B29C55/005—Shaping by stretching, e.g. drawing through a die; Apparatus therefor characterised by the choice of materials
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29D—PRODUCING PARTICULAR ARTICLES FROM PLASTICS OR FROM SUBSTANCES IN A PLASTIC STATE
- B29D22/00—Producing hollow articles
- B29D22/003—Containers for packaging, storing or transporting, e.g. bottles, jars, cans, barrels, tanks
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C48/00—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor
- B29C48/001—Combinations of extrusion moulding with other shaping operations
- B29C48/0018—Combinations of extrusion moulding with other shaping operations combined with shaping by orienting, stretching or shrinking, e.g. film blowing
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C48/00—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor
- B29C48/03—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor characterised by the shape of the extruded material at extrusion
- B29C48/09—Articles with cross-sections having partially or fully enclosed cavities, e.g. pipes or channels
- B29C48/10—Articles with cross-sections having partially or fully enclosed cavities, e.g. pipes or channels flexible, e.g. blown foils
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C48/00—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor
- B29C48/16—Articles comprising two or more components, e.g. co-extruded layers
- B29C48/18—Articles comprising two or more components, e.g. co-extruded layers the components being layers
- B29C48/21—Articles comprising two or more components, e.g. co-extruded layers the components being layers the layers being joined at their surfaces
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29K—INDEXING SCHEME ASSOCIATED WITH SUBCLASSES B29B, B29C OR B29D, RELATING TO MOULDING MATERIALS OR TO MATERIALS FOR MOULDS, REINFORCEMENTS, FILLERS OR PREFORMED PARTS, e.g. INSERTS
- B29K2003/00—Use of starch or derivatives as moulding material
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29K—INDEXING SCHEME ASSOCIATED WITH SUBCLASSES B29B, B29C OR B29D, RELATING TO MOULDING MATERIALS OR TO MATERIALS FOR MOULDS, REINFORCEMENTS, FILLERS OR PREFORMED PARTS, e.g. INSERTS
- B29K2067/00—Use of polyesters or derivatives thereof, as moulding material
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29K—INDEXING SCHEME ASSOCIATED WITH SUBCLASSES B29B, B29C OR B29D, RELATING TO MOULDING MATERIALS OR TO MATERIALS FOR MOULDS, REINFORCEMENTS, FILLERS OR PREFORMED PARTS, e.g. INSERTS
- B29K2995/00—Properties of moulding materials, reinforcements, fillers, preformed parts or moulds
- B29K2995/0037—Other properties
- B29K2995/0059—Degradable
- B29K2995/006—Bio-degradable, e.g. bioabsorbable, bioresorbable or bioerodible
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
- Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
- Y10T428/00—Stock material or miscellaneous articles
- Y10T428/13—Hollow or container type article [e.g., tube, vase, etc.]
- Y10T428/1334—Nonself-supporting tubular film or bag [e.g., pouch, envelope, packet, etc.]
- Y10T428/1345—Single layer [continuous layer]
Definitions
- the present invention relates to a monoaxial or biaxial cold stretching process of a blown film to produce biodegradable films characterized by improved mechanical properties.
- biodegradable films to produce products such as bags for separate waste collection, shopping bags, mulch film, diapers, sanitary articles and the like, has grown rapidly in recent years.
- products deriving from the processing of biodegradable films obtained from starch and polyester based compositions are currently widely used on the market.
- the reason for this increased spread of starch based mixtures within the scope of biodegradable plastic materials is linked in particular to the need to use raw materials deriving from renewable sources.
- An object of the present invention is to provide a process for the production of biodegradable films which makes it possible to obtain products with the appropriate properties related to performance, while at the same time limiting the production costs of said films.
- the present invention therefore relates to a monoaxial or biaxial cold stretching process for the production of biodegradable films which makes it possible to produce biodegradable films characterized by reduced thickness and superior mechanical properties.
- the processes to stretch plastic films are known: these are processes to orient films in a longitudinal and/or transverse direction (oriented and bi-oriented films) which allow uniform distribution of the polymer molecules, influencing the mechanical properties of the film in the various directions to increase the stiffness thereof.
- the prior art also describes stretching processes applied to biodegradable films, in particular deriving from starch based compositions.
- EP-0 537 657 describes a stretching process of mono-layer or multi-layer films with at least one layer composed of thermoplastically processable starch, wherein the film is monoaxially or biaxially stretched with a stretch ratio between 1:4 and 1:10, preferably 1:6 and 1:8.5 and even more preferably with a ratio of 1:7 and 1:7.5.
- the stretching process is performed on an essentially anhydrous film as the initial polymers are dried prior to melting or dehydrated during extrusion. Stretching is performed (see Table 1 of EP-0 537 657) within a temperature range of approximately 90-130° C. At stretch ratios below 1:4 the properties of the film decline significantly.
- This process generically provides for the possibility of stretching at ambient temperature, although always and only with an anhydrous starch based mixture and with stretch ratios of at least 1:4.
- the process described there is therefore costly from the viewpoint of energy consumption.
- the stretched films obtained according to said process although showing an increase in the ultimate tensile strength values, show a considerable increase in the elastic modulus values, making these films particularly stiff, although fragile and with a low tearing strength.
- WO 97/22459 discloses a process for producing oriented polyhydroxyalkanoate (PHA) comprising a first stretch at a temperature below 60° C. and a second stretch at a temperature of 60-110° C.
- the first stretch is carried out before the polymer has fully solidified; the extent of the first stretch is incomplete to permit further stretching.
- WO 01/30893 discloses a process for producing polymer products by stretching compositions comprising a biodegradable polyhydroxyalkanoate at a temperature of from (Tg+20° C.) to (Tm ⁇ 20° C.). Since Tm of the relevant polymer is generally above 100° C., it follows that the stretching process can be carried out also at a temperature above 80° C.
- cold stretching is intended as stretching performed on the unmelted biodegradable polymer material. More specifically, cold stretching is intended, with reference to films with thickness below 70 ⁇ m, as stretching performed at a temperature ranging from 10 to 50° C., preferably between 15 and 40° C. and even more preferably between 20 and 30° C. For films with thickness above 70 ⁇ m, the temperatures required for cold stretching may exceed the ranges mentioned above.
- the process according to the present invention is preferably performed at ambient temperatures but, in relation to the thickness of the films to be subjected to stretching and the composition of the biodegradable polymer material, heating may in fact be necessary to promote the stretching process and make it homogeneous.
- biodegradable films obtained with the process according to the present invention are particularly suitable to be used in various fields of application, for example for shopping bags, films for sanitary products and mulching films.
- the process according to the present invention is directed to films produced from biodegradable polymer materials.
- the biodegradable polymer materials that can be used in the process of the present invention may be of various nature, such as, for example, biodegradable aliphatic polyesters, aliphatic-aromatic polyesters, polyhydroxyalkanoates, polyhydroxyacids, polyesteramides.
- Particularly preferred are biodegradable polymers showing values of the Modulus (measured on blown films with 30 ⁇ m thickness) comprised in the range of 40-300 MPa, preferably 60-250 MPa and more preferably 100-200 MPa.
- biodegradability means biodegradability according to the EN 13432 standard.
- compositions with at least one polysaccharide derivative and at least one biodegradable polymer in particular a biodegradable aliphatic or aliphatic-aromatic polymer from dicarboxylic acid/diol and/or hydroxy acid.
- polysaccharide comprises in particular starch, cellulose and its derivatives (such as for example cellulose acetate, cellulose proprionate, cellulose acetate propionate, cellulose butyrate), alginates.
- Polysaccharides can be combined also with proteins.
- films produced from a composition containing starch and at least one biodegradable aliphatic or aliphatic-aromatic polymer from dicarboxylic acid/diol and/or hydroxy acid are particularly preferred.
- diacids examples include succinic, oxalic, malonic, glutaric, adipic, pimelic, suberic, undecanoic, dodecanoic, azelaic, sebacic and brassylic acid. Particularly preferred are adipic acid, azelaic acid, sebacic acid and brassylic acid or their mixtures.
- glycols are ethylene glycol, diethylene glycol, triethylene glycol, polyethylene glycol.
- the compounds can be used alone or in a mixture.
- Typical hydroxy acids include glycolic acid, lactic acid, 3-hydroxybutyric, 4-hydroxybutyric, 3-hydroxyvaleric, 4-hydroxyvaleric, 6-hydroxycaproic, and also include cyclic esters of hydroxycarboxylic acids, such as glycolide, dimers of glycolic acid, ⁇ -caprolactone and 6-hydroxycaproic acid.
- the biodegradable polymer used in the films subjected to the process according to the present invention preferably contains a polyfunctional aromatic compound such as a phthalic acid, in particular terephthalic acid, bisphenol A, hydroquinone and the like.
- the biodegradable aliphatic or aliphatic-aromatic polymer can advantageously be a thermoplastic copolyester of the saturated-unsaturated type obtained from dicarboxylic acids, diols and unsaturated acids of both natural and synthetic origin
- the biodegradable aliphatic or aliphatic-aromatic polymer can be obtained with high molecular weights by adding various organic peroxides in the course of its treatment with peroxide during extrusion.
- polymers with the aromatic part constituted by terephthalic acid and the aliphatic part constituted by diacid diols and/or hydroxy acids with branched and straight aliphatic chain C 2 -C 20 (if necessary chain extended with isocyanates, anhydrides or epoxides), and in particular polyesters based on terephthalic acid, adipidic acid or sebacic acid, or azelaic acid and butandiol.
- Particularly preferred polymers are polybutylenadipate-co-terephtalate produced by BASF A.G. and marketed with the trademark Ecoflex® and polybutylenadipate-co-terephtalate produced by Eastman under the tradename Eastarbio®.
- starch is intended as native starch, preferably corn, potato, tapioca, rice, wheat or pea starch and also starch with high amylose contents and “waxy” starches.
- Flour, grits, physically and chemically modified starches such as ethoxylated starches, oxypropylated starches, acetate starches, butyrate starches, propionate starches, cationic starches, oxidized starches, reticulated starches, gelatinized starches, destructured starches and starches complexed by polymer structures can also be used. Particularly preferred are destructured starch based films.
- Suitable plasticizers are for example those described in EP-0 575 349, the content of which is intended as incorporated in the present invention. Particularly suitable are glycerol, sorbitol, mannitol, erythritol, polyvinyl alcohol with low molecular weight, as well as the oxyethylated and oxypropylated derivatives of the aforesaid compounds, citrates and acetins.
- the starting compositions can also contain suitable additives, such as lubricating or dispersing agents, dyes, fillers, etc.
- Films suitable to be subjected to the present process can be both mono-layer and multi-layer.
- said films can be constituted by at least one layer of starch based material and by at least one layer of biodegradable polyester as is or mixed with other polyesters.
- the cold stretching process according to the present invention makes it possible to produce biodegradable films with reduced thickness and with remarkable mechanical properties. These films are therefore useful to produce products such as all kinds and shapes of bags, in particular bags for separate waste collection, shopping bags, mulch film, diapers, sanitary articles. In particular, it is possible to produce stretched films with thickness in the interval ranging from 5 to 60 ⁇ m, preferably from 6 to 40 ⁇ m and even more preferably from 8 to 30 ⁇ m.
- films produced according to the present process are particularly advantageous for the production of shopping bags.
- Films produced according to the present process can also be advantageously be used as reduced thickness backsheets in diapers, as perforated topsheets in sanitary articles and as films for primary and secondary outer packaging materials.
- FIG. 1 shows the Stress-Strain curves of said stretched films and of the film as is.
- FIG. 2 shows the enlarged detail of the initial part of the curve relative to the stretched film with a ratio of 1:2 which has a characteristic bimodal trend.
- FIGS. 3 , 4 and 5 instead show the graphs relative to the values of the ultimate tensile strength, the yield strength and modulus tests performed on said films.
- Table 1 shows the values of the mechanical tests relative to the film as such, with thickness of 31 ⁇ m and 19 ⁇ m, compared to the values of the 31 ⁇ m cold stretched film stretched at different temperatures and with stretch ratio of 1:2 until reaching a thickness of 19 ⁇ m.
- the tests to determine the Tensile Strength, Yield Strength and Modulus were carried out according to the standard ASTM D 882.
- the puncture strength test was instead carried out on a specimen with a diameter of 7.6 cm positioned on an annular support.
- the film was tested at 23° C. and 50% of relative humidity with the punch at a speed of 1 m/sec.
- the film has also been stretched at 15° and 45° C.
Abstract
Description
- The present invention relates to a monoaxial or biaxial cold stretching process of a blown film to produce biodegradable films characterized by improved mechanical properties.
- The use of biodegradable films to produce products such as bags for separate waste collection, shopping bags, mulch film, diapers, sanitary articles and the like, has grown rapidly in recent years. In particular, products deriving from the processing of biodegradable films obtained from starch and polyester based compositions are currently widely used on the market. The reason for this increased spread of starch based mixtures within the scope of biodegradable plastic materials is linked in particular to the need to use raw materials deriving from renewable sources.
- It is important to attempt to reduce the costs of these films in order to allow faster and more widespread penetration of biodegradable materials in the market, also in view of an increased social awareness of problems related to sustainable and eco-compatible development.
- An object of the present invention is to provide a process for the production of biodegradable films which makes it possible to obtain products with the appropriate properties related to performance, while at the same time limiting the production costs of said films. The present invention therefore relates to a monoaxial or biaxial cold stretching process for the production of biodegradable films which makes it possible to produce biodegradable films characterized by reduced thickness and superior mechanical properties.
- The processes to stretch plastic films (that is, sheets with a thickness which is generally below 200 μm), are known: these are processes to orient films in a longitudinal and/or transverse direction (oriented and bi-oriented films) which allow uniform distribution of the polymer molecules, influencing the mechanical properties of the film in the various directions to increase the stiffness thereof. The prior art also describes stretching processes applied to biodegradable films, in particular deriving from starch based compositions.
- EP-0 537 657 describes a stretching process of mono-layer or multi-layer films with at least one layer composed of thermoplastically processable starch, wherein the film is monoaxially or biaxially stretched with a stretch ratio between 1:4 and 1:10, preferably 1:6 and 1:8.5 and even more preferably with a ratio of 1:7 and 1:7.5. The stretching process is performed on an essentially anhydrous film as the initial polymers are dried prior to melting or dehydrated during extrusion. Stretching is performed (see Table 1 of EP-0 537 657) within a temperature range of approximately 90-130° C. At stretch ratios below 1:4 the properties of the film decline significantly. This process generically provides for the possibility of stretching at ambient temperature, although always and only with an anhydrous starch based mixture and with stretch ratios of at least 1:4. The process described there is therefore costly from the viewpoint of energy consumption. Moreover, the stretched films obtained according to said process, although showing an increase in the ultimate tensile strength values, show a considerable increase in the elastic modulus values, making these films particularly stiff, although fragile and with a low tearing strength.
- WO 97/22459 discloses a process for producing oriented polyhydroxyalkanoate (PHA) comprising a first stretch at a temperature below 60° C. and a second stretch at a temperature of 60-110° C. The first stretch is carried out before the polymer has fully solidified; the extent of the first stretch is incomplete to permit further stretching.
- WO 01/30893 discloses a process for producing polymer products by stretching compositions comprising a biodegradable polyhydroxyalkanoate at a temperature of from (Tg+20° C.) to (Tm−20° C.). Since Tm of the relevant polymer is generally above 100° C., it follows that the stretching process can be carried out also at a temperature above 80° C.
- It can be appreciated that the stretch processes described in these two patent documents are carried out at a relatively high temperature, as known in the art. This involves a significant energy consumption.
- The drawbacks mentioned above are now surprisingly overcome according to the present invention by subjecting a biodegradable film, after its production by bubble blowing, to a cold stretching process with a stretch ratio greater than 1:1 and less than 1:4, in particular between 1:1.2 and 1:3, and even more particularly between 1:1.5 and 1:2.5, said process making it possible to increase the ultimate tensile strength and yield strength values and to keep the elastic modulus and puncture strength at more or less constant values.
- Within the scope of the present invention, cold stretching is intended as stretching performed on the unmelted biodegradable polymer material. More specifically, cold stretching is intended, with reference to films with thickness below 70 μm, as stretching performed at a temperature ranging from 10 to 50° C., preferably between 15 and 40° C. and even more preferably between 20 and 30° C. For films with thickness above 70 μm, the temperatures required for cold stretching may exceed the ranges mentioned above. The process according to the present invention is preferably performed at ambient temperatures but, in relation to the thickness of the films to be subjected to stretching and the composition of the biodegradable polymer material, heating may in fact be necessary to promote the stretching process and make it homogeneous.
- The cold stretching process according to the present invention can be implemented on various types of film, for example on single-sheet, single-fold films or directly on tubular films. The cold stretching process according to the present invention can in fact be implemented both discontinuously and in line with the bubble blowing process. If the process is performed in line with the bubble blowing process, this takes place beyond the chill line, that is, subsequent to the height beyond which the bubble has solidified. In this case double bubble blowing processes can also be used.
- The biodegradable films obtained with the process according to the present invention are particularly suitable to be used in various fields of application, for example for shopping bags, films for sanitary products and mulching films.
- The process according to the present invention is directed to films produced from biodegradable polymer materials. The biodegradable polymer materials that can be used in the process of the present invention may be of various nature, such as, for example, biodegradable aliphatic polyesters, aliphatic-aromatic polyesters, polyhydroxyalkanoates, polyhydroxyacids, polyesteramides. Particularly preferred are biodegradable polymers showing values of the Modulus (measured on blown films with 30 μm thickness) comprised in the range of 40-300 MPa, preferably 60-250 MPa and more preferably 100-200 MPa. In the present description biodegradability means biodegradability according to the EN 13432 standard.
- Particularly suitable to be subjected to the process of the invention are films produced from compositions with at least one polysaccharide derivative and at least one biodegradable polymer, in particular a biodegradable aliphatic or aliphatic-aromatic polymer from dicarboxylic acid/diol and/or hydroxy acid. The term polysaccharide comprises in particular starch, cellulose and its derivatives (such as for example cellulose acetate, cellulose proprionate, cellulose acetate propionate, cellulose butyrate), alginates. Polysaccharides can be combined also with proteins.
- Particularly preferred are films produced from a composition containing starch and at least one biodegradable aliphatic or aliphatic-aromatic polymer from dicarboxylic acid/diol and/or hydroxy acid.
- Examples of diacids are succinic, oxalic, malonic, glutaric, adipic, pimelic, suberic, undecanoic, dodecanoic, azelaic, sebacic and brassylic acid. Particularly preferred are adipic acid, azelaic acid, sebacic acid and brassylic acid or their mixtures.
- Specific glycols are ethylene glycol, diethylene glycol, triethylene glycol, polyethylene glycol. 1,2- and 1,3-propylene glycol, dipropylene glycol, 1,3-butandiol, 1,4-butandiol, 3-methyl-1,5-pentandiol, 1,6-hexandiol, 1,9-nonandiol, 1,10-decandiol, 1,11-undecandiol, 1,12-dodecandiol, 1,13-tridecandiol, neopentyl glycol, polytetramethylene glycol, 1,4-cyclohexandimethanol and cyclohexandiol. The compounds can be used alone or in a mixture. Typical hydroxy acids include glycolic acid, lactic acid, 3-hydroxybutyric, 4-hydroxybutyric, 3-hydroxyvaleric, 4-hydroxyvaleric, 6-hydroxycaproic, and also include cyclic esters of hydroxycarboxylic acids, such as glycolide, dimers of glycolic acid, ε-caprolactone and 6-hydroxycaproic acid.
- With regard to the aromatic part, the biodegradable polymer used in the films subjected to the process according to the present invention preferably contains a polyfunctional aromatic compound such as a phthalic acid, in particular terephthalic acid, bisphenol A, hydroquinone and the like.
- The biodegradable aliphatic or aliphatic-aromatic polymer can advantageously be a thermoplastic copolyester of the saturated-unsaturated type obtained from dicarboxylic acids, diols and unsaturated acids of both natural and synthetic origin
- The biodegradable aliphatic or aliphatic-aromatic polymer can be obtained with high molecular weights by adding various organic peroxides in the course of its treatment with peroxide during extrusion.
- Particularly preferred are polymers with the aromatic part constituted by terephthalic acid and the aliphatic part constituted by diacid diols and/or hydroxy acids, with branched and straight aliphatic chain C2-C20 (if necessary chain extended with isocyanates, anhydrides or epoxides), and in particular polyesters based on terephthalic acid, adipidic acid or sebacic acid, or azelaic acid and butandiol.
- Particularly preferred polymers are polybutylenadipate-co-terephtalate produced by BASF A.G. and marketed with the trademark Ecoflex® and polybutylenadipate-co-terephtalate produced by Eastman under the tradename Eastarbio®.
- With reference to the starch component of films to be subjected to the process according to the present invention, the term starch is intended as native starch, preferably corn, potato, tapioca, rice, wheat or pea starch and also starch with high amylose contents and “waxy” starches. Flour, grits, physically and chemically modified starches such as ethoxylated starches, oxypropylated starches, acetate starches, butyrate starches, propionate starches, cationic starches, oxidized starches, reticulated starches, gelatinized starches, destructured starches and starches complexed by polymer structures can also be used. Particularly preferred are destructured starch based films.
- Advantageously, the mixture to produce the film may contain one or more plasticizers.
- Suitable plasticizers are for example those described in EP-0 575 349, the content of which is intended as incorporated in the present invention. Particularly suitable are glycerol, sorbitol, mannitol, erythritol, polyvinyl alcohol with low molecular weight, as well as the oxyethylated and oxypropylated derivatives of the aforesaid compounds, citrates and acetins. The starting compositions can also contain suitable additives, such as lubricating or dispersing agents, dyes, fillers, etc.
- Films suitable to be subjected to the present process can be both mono-layer and multi-layer. In the case of multi-layer films, said films can be constituted by at least one layer of starch based material and by at least one layer of biodegradable polyester as is or mixed with other polyesters.
- The cold stretching process according to the present invention makes it possible to produce biodegradable films with reduced thickness and with remarkable mechanical properties. These films are therefore useful to produce products such as all kinds and shapes of bags, in particular bags for separate waste collection, shopping bags, mulch film, diapers, sanitary articles. In particular, it is possible to produce stretched films with thickness in the interval ranging from 5 to 60 μm, preferably from 6 to 40 μm and even more preferably from 8 to 30 μm.
- In view of the high yield strength values, the films produced according to the present process are particularly advantageous for the production of shopping bags. Films produced according to the present process can also be advantageously be used as reduced thickness backsheets in diapers, as perforated topsheets in sanitary articles and as films for primary and secondary outer packaging materials.
- A composition constituted by
-
Corn starch 29.5% Polybutylenadipate-co-terephtalate 64.0% (47% terephtalate; 53% adipate; MFI = 2.5 dl/g) Glycerol 6.2% Erucamide 0.3% - was fed, with the addition of 2.2% of water, to a blown film processing unit obtaining a film with thickness of approximately 31μ. Said film was subsequently subjected to a stretching process at ambient temperature (23° C., 50% relative humidity) and with various stretch ratios, in particular 1:2, 1:3 and 1:4.
-
FIG. 1 shows the Stress-Strain curves of said stretched films and of the film as is. -
FIG. 2 shows the enlarged detail of the initial part of the curve relative to the stretched film with a ratio of 1:2 which has a characteristic bimodal trend. -
FIGS. 3 , 4 and 5 instead show the graphs relative to the values of the ultimate tensile strength, the yield strength and modulus tests performed on said films. - Finally, Table 1 shows the values of the mechanical tests relative to the film as such, with thickness of 31 μm and 19 μm, compared to the values of the 31 μm cold stretched film stretched at different temperatures and with stretch ratio of 1:2 until reaching a thickness of 19 μm.
- The tests to determine the Tensile Strength, Yield Strength and Modulus were carried out according to the standard ASTM D 882. The puncture strength test was instead carried out on a specimen with a diameter of 7.6 cm positioned on an annular support. The puncture punch with semi-circular head had a Ø=3 mm. The film was tested at 23° C. and 50% of relative humidity with the punch at a speed of 1 m/sec. The film has also been stretched at 15° and 45° C.
- The data provided below show that the stretching process according to the present invention makes it possible to obtain a remarkable increase in the mechanical properties with respect to the unstretched biodegradable film.
-
TABLE 1 Tensile Yield E Puncture Strength σb Strength σy Modulus Test Enb Film type (Mpa) (Mpa) (Mpa) (J/mm) NFO1U 31 μm 25 11 135 1.81 NFO1U 19 μm 21 9 130 1.72 NFO1U 19 μm from 46 24 140 1.84 stretched 31 μm film (23° C.) NFO1U 19 μm from 42 21 138 1.82 stretched 31 μm film (15° C.) NFO1U 19 μm from 49 26 143 1.85 stretched 31 μm film (45° C.)
Claims (21)
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
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US14/036,215 US20140106097A1 (en) | 2004-06-09 | 2013-09-25 | Process for the production of biodegradable films having improved mechanical properties |
Applications Claiming Priority (5)
Application Number | Priority Date | Filing Date | Title |
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ITMI2004A001150 | 2004-06-09 | ||
IT001150A ITMI20041150A1 (en) | 2004-06-09 | 2004-06-09 | PEARL PROCESS PRODUCTION OF BIODEGRADABLE FILMS HAVING IMPROVED MECHANICAL PROPERTIES |
US11/570,279 US20070241483A1 (en) | 2004-06-09 | 2005-06-08 | Process for The Production of Biodegradable Films Having Improved Mechanical Properties |
PCT/EP2005/006146 WO2005120808A1 (en) | 2004-06-09 | 2005-06-08 | Process for the production of biodegradable films having improved mechanical properties |
US14/036,215 US20140106097A1 (en) | 2004-06-09 | 2013-09-25 | Process for the production of biodegradable films having improved mechanical properties |
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US11/570,279 Continuation US20070241483A1 (en) | 2004-06-09 | 2005-06-08 | Process for The Production of Biodegradable Films Having Improved Mechanical Properties |
PCT/EP2005/006146 Continuation WO2005120808A1 (en) | 2004-06-09 | 2005-06-08 | Process for the production of biodegradable films having improved mechanical properties |
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US20140106097A1 true US20140106097A1 (en) | 2014-04-17 |
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Family Applications (2)
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US11/570,279 Abandoned US20070241483A1 (en) | 2004-06-09 | 2005-06-08 | Process for The Production of Biodegradable Films Having Improved Mechanical Properties |
US14/036,215 Abandoned US20140106097A1 (en) | 2004-06-09 | 2013-09-25 | Process for the production of biodegradable films having improved mechanical properties |
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US11/570,279 Abandoned US20070241483A1 (en) | 2004-06-09 | 2005-06-08 | Process for The Production of Biodegradable Films Having Improved Mechanical Properties |
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US (2) | US20070241483A1 (en) |
EP (1) | EP1755864B2 (en) |
AT (1) | ATE534505T1 (en) |
AU (1) | AU2005251905B9 (en) |
CA (1) | CA2567323A1 (en) |
ES (1) | ES2376107T5 (en) |
IT (1) | ITMI20041150A1 (en) |
NO (1) | NO338782B1 (en) |
PL (1) | PL1755864T5 (en) |
WO (1) | WO2005120808A1 (en) |
Families Citing this family (15)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2007022080A2 (en) * | 2005-08-12 | 2007-02-22 | Michigan State University | Biodegradable polymeric nanocomposite compositions particularly for packaging |
BRPI0600685A (en) * | 2006-02-24 | 2007-11-20 | Phb Ind Sa | environmentally degradable polymeric blend and its process of obtaining |
US8592641B2 (en) | 2006-12-15 | 2013-11-26 | Kimberly-Clark Worldwide, Inc. | Water-sensitive biodegradable film |
ITGE20070044A1 (en) * | 2007-05-23 | 2008-11-24 | Awax Progettazione | EXTENSIBLE BIODEGRADABLE FILM WITH IMPROVED CHARACTERISTICS. |
US8329977B2 (en) | 2007-08-22 | 2012-12-11 | Kimberly-Clark Worldwide, Inc. | Biodegradable water-sensitive films |
JP4972012B2 (en) * | 2008-02-28 | 2012-07-11 | 株式会社クレハ | Sequential biaxially stretched polyglycolic acid film, method for producing the same, and multilayer film |
US8415021B2 (en) * | 2010-01-20 | 2013-04-09 | E I Du Pont De Nemours And Company | Biodegradable starch-containing composition with improved tear strength |
US8409677B2 (en) * | 2010-01-20 | 2013-04-02 | E I Du Pont De Nemours And Company | Biodegradable starch-containing blend |
US8907155B2 (en) * | 2010-11-19 | 2014-12-09 | Kimberly-Clark Worldwide, Inc. | Biodegradable and flushable multi-layered film |
US9334360B2 (en) | 2011-07-15 | 2016-05-10 | Sabic Global Technologies B.V. | Color-stabilized biodegradable aliphatic-aromatic copolyesters, methods of manufacture, and articles thereof |
US8877862B2 (en) | 2011-07-15 | 2014-11-04 | Saudi Basic Industries Corporation | Method for color stabilization of poly(butylene-co-adipate terephthalate |
US9718258B2 (en) | 2011-12-20 | 2017-08-01 | Kimberly-Clark Worldwide, Inc. | Multi-layered film containing a biopolymer |
US9327438B2 (en) | 2011-12-20 | 2016-05-03 | Kimberly-Clark Worldwide, Inc. | Method for forming a thermoplastic composition that contains a plasticized starch polymer |
IT201900006282A1 (en) | 2019-04-23 | 2020-10-23 | Novamont Spa | BIODEGRADABLE FILMS WITH IMPROVED MECHANICAL PROPERTIES |
DE102021101538A1 (en) | 2021-01-25 | 2022-07-28 | Bio-Tec Biologische Naturverpackungen Gmbh & Co.Kg | Polymer composition containing pea starch |
Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4427614A (en) * | 1980-04-30 | 1984-01-24 | Imperial Chemical Industries Plc | 3-Hydroxybutyric acid polymers |
JPH07290564A (en) * | 1994-04-28 | 1995-11-07 | Showa Denko Kk | Aliphatic polyester stretched molded object and production thereof |
US6372331B1 (en) * | 1998-06-03 | 2002-04-16 | Mitsubishi Plastics, Inc. | Biodegradable card |
US6573340B1 (en) * | 2000-08-23 | 2003-06-03 | Biotec Biologische Naturverpackungen Gmbh & Co. Kg | Biodegradable polymer films and sheets suitable for use as laminate coatings as well as wraps and other packaging materials |
Family Cites Families (30)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3801404A (en) * | 1970-10-28 | 1974-04-02 | Celanese Corp | Novel open-celled microporous film |
US3839240A (en) * | 1971-03-18 | 1974-10-01 | Celanese Corp | High melt index microporous films |
US3880966A (en) * | 1971-09-23 | 1975-04-29 | Celanese Corp | Corona treated microporous film |
US4151245A (en) * | 1972-12-06 | 1979-04-24 | Matsushita Electric Industrial Co., Ltd. | Method for stretching a thermo-softening high molecular film |
US3843761A (en) * | 1973-05-30 | 1974-10-22 | Celanese Corp | Process for preparing a thermoplastic microporous film involving a cold stretching step and multiple hot stretching steps |
US4350655A (en) * | 1977-05-05 | 1982-09-21 | Biax Fiberfilm | Process for producing highly porous thermoplastic films |
GB2007685B (en) * | 1977-10-11 | 1982-05-12 | Asahi Dow Ltd | Composition for drawn film cold drawn film made of said composition and process for manufacture of said film |
AU533447B2 (en) * | 1978-12-18 | 1983-11-24 | Asahi Kasei Kogyo Kabushiki Kaisha | Stretching multi layer film |
JPS6169431A (en) * | 1984-09-14 | 1986-04-10 | Teijin Ltd | Stretching method of poly(beta-hydroxybutyric acid) molded product |
US5216050A (en) * | 1988-08-08 | 1993-06-01 | Biopak Technology, Ltd. | Blends of polyactic acid |
US5176953A (en) * | 1990-12-21 | 1993-01-05 | Amoco Corporation | Oriented polymeric microporous films |
CA2071422C (en) * | 1991-09-06 | 1996-06-25 | Jack N. Shirrell | Method for making prestretched film |
US5594076A (en) * | 1991-09-24 | 1997-01-14 | The Pennsylvania Research Foundation | Hydrodegradable polyesters |
US5256711A (en) * | 1991-10-04 | 1993-10-26 | Director-General Of Agency Of Industrial Science | Starch-containing biodegradable plastic and method of producing same |
DE4134190A1 (en) † | 1991-10-16 | 1993-04-22 | Tomka Ivan | METHOD FOR IMPROVING THE MECHANICAL PROPERTIES OF ONE-OR MULTILAYER FOILS |
DE69317423T2 (en) * | 1992-06-26 | 1998-07-09 | Procter & Gamble | Biodegradable, liquid-impermeable multilayer film composition |
JPH083333A (en) * | 1994-06-22 | 1996-01-09 | Tokuyama Corp | Melt-extruded film of biodegradable aliphatic polyester and bag comprising the same |
JPH07205278A (en) * | 1994-01-11 | 1995-08-08 | Mitsubishi Plastics Ind Ltd | Production of stretched film of polylactic acid polymer |
JP2882756B2 (en) * | 1994-10-12 | 1999-04-12 | 昭和高分子株式会社 | Stretched hollow molded article comprising an aliphatic polyester composition |
EP0736563A1 (en) * | 1995-04-07 | 1996-10-09 | SAFTA S.p.A. | Process for the manufacture of totally bio-decomposable films with high mechanical characteristics and relevant products and applications |
US5731402A (en) * | 1995-04-25 | 1998-03-24 | Tokuyama Corporation | Biodegradable aliphatic polyester, melt-extrusion film thereof, and process for the production thereof |
GB9526165D0 (en) * | 1995-12-21 | 1996-02-21 | Zeneca Ltd | Oriented polyester |
US6124384A (en) * | 1997-08-19 | 2000-09-26 | Mitsui Chemicals, Inc. | Composite resin composition |
EP1025152A1 (en) * | 1997-10-31 | 2000-08-09 | Monsanto Company | Plasticized polyhydroxyalkanoate compositions and methods for their use in the production of shaped polymeric articles |
DE19847909A1 (en) † | 1998-10-19 | 2000-04-20 | Basf Ag | Process to improve the lifetime of biodegradable polymer based filaments, fiber or film useful for packaging, comprises stretching during or after production |
WO2001030893A1 (en) * | 1999-10-28 | 2001-05-03 | The Procter & Gamble Company | Methods for preparing soft and elastic biodegradable polyhydroxyalkanoate copolymer compositions and polymer products comprising such compositions |
DE10054650A1 (en) † | 2000-11-03 | 2002-05-08 | Basf Ag | Back sheet for hygiene articles, e.g. disposable diapers, contains a sheet of biodegradable polymer with high water vapor permeability and flexibility, consisting of a special partly aromatic polyester |
US6610025B2 (en) * | 2001-08-06 | 2003-08-26 | The Procter & Gamble Company | Tampon applicator arrangement |
WO2003070450A1 (en) * | 2002-02-21 | 2003-08-28 | Riken | High-strength film of polyhydroxyalkanoic acid and process for producing the same |
US7153569B2 (en) * | 2004-03-19 | 2006-12-26 | Kimberly-Clark Worldwide, Inc. | Biodegradable aliphatic-aromatic copolyester films |
-
2004
- 2004-06-09 IT IT001150A patent/ITMI20041150A1/en unknown
-
2005
- 2005-06-08 WO PCT/EP2005/006146 patent/WO2005120808A1/en active Application Filing
- 2005-06-08 CA CA002567323A patent/CA2567323A1/en not_active Abandoned
- 2005-06-08 US US11/570,279 patent/US20070241483A1/en not_active Abandoned
- 2005-06-08 PL PL05756031T patent/PL1755864T5/en unknown
- 2005-06-08 ES ES05756031.0T patent/ES2376107T5/en active Active
- 2005-06-08 AU AU2005251905A patent/AU2005251905B9/en not_active Ceased
- 2005-06-08 EP EP05756031.0A patent/EP1755864B2/en active Active
- 2005-06-08 AT AT05756031T patent/ATE534505T1/en active
-
2007
- 2007-01-08 NO NO20070126A patent/NO338782B1/en not_active IP Right Cessation
-
2013
- 2013-09-25 US US14/036,215 patent/US20140106097A1/en not_active Abandoned
Patent Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4427614A (en) * | 1980-04-30 | 1984-01-24 | Imperial Chemical Industries Plc | 3-Hydroxybutyric acid polymers |
JPH07290564A (en) * | 1994-04-28 | 1995-11-07 | Showa Denko Kk | Aliphatic polyester stretched molded object and production thereof |
US6372331B1 (en) * | 1998-06-03 | 2002-04-16 | Mitsubishi Plastics, Inc. | Biodegradable card |
US6573340B1 (en) * | 2000-08-23 | 2003-06-03 | Biotec Biologische Naturverpackungen Gmbh & Co. Kg | Biodegradable polymer films and sheets suitable for use as laminate coatings as well as wraps and other packaging materials |
Also Published As
Publication number | Publication date |
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CA2567323A1 (en) | 2005-12-22 |
PL1755864T3 (en) | 2012-04-30 |
EP1755864B1 (en) | 2011-11-23 |
EP1755864A1 (en) | 2007-02-28 |
US20070241483A1 (en) | 2007-10-18 |
ITMI20041150A1 (en) | 2004-09-09 |
ES2376107T3 (en) | 2012-03-09 |
WO2005120808A1 (en) | 2005-12-22 |
AU2005251905A1 (en) | 2005-12-22 |
NO338782B1 (en) | 2016-10-17 |
AU2005251905B9 (en) | 2012-02-02 |
ATE534505T1 (en) | 2011-12-15 |
EP1755864B2 (en) | 2014-08-13 |
NO20070126L (en) | 2007-01-08 |
PL1755864T5 (en) | 2015-01-30 |
AU2005251905B2 (en) | 2011-05-19 |
ES2376107T5 (en) | 2014-09-30 |
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